Throatless glass furnace



2 Sheets-Sheet 1 INVENTOR HK. fiu aeqx/r ATTORNEYS" Aug. 3, 1965 H. 1..PENBERTHY THROATLESS GLASS FURNACE Filed March 9, 1955 Aug. 3, 1965 H.L. PENBERTHY THROATLESS GLASS FURNACE Filed March 9, 1955 2 Sheets-Sheet2 ATTORNEYS ticn irly to glass furnaces having no or tge Wall or throattherein.

nous process glass manufacture the In standard cor material to e treatedis ch rged at one end of the and removed at o" or end in the to 2 ectedsuccessively in its passe nnished glass, be "hrongh the fi ace to theoceretions of melting,

n" 2 3 7 e F and ot coonng toward a v/ g temperature. iii nace that can"out this caration of the class -*n include three zones roughly corpenning LO the e and general y ref rred to as me l lining and working orcc itioning zones. 'equently some of the zones are contained, but inmore modern furnaces be have been erected attempt to isolate W steps ofin tnese furnaces a bridge Wall is conventions y located between thrneltir" and this wall is ovided v li a snbnrer ed throat which perglass therethro': The Dose of vent tinzneltcd glass from entering the fseqnently the condition and possibly get Ware. l lc-wever, even with useof such has been clifficu to prevent all ted batch from enteri g theconditi ning zone and in ord'nary usage the flow or glass lire-ugh thethroat exercises strong eroding action on edges of the Well introducingstones and other impurities into the glass and fairly r 'Jidly wearawaythe wall so that reglacenient is frec sently necessary.

This problem has been recognized and several attempts have been made tooperate furnaces .vitl -t bridge Walls iner described in Anrslet PatentNumies were experienced, how ver, in prev nting unmelted batch frontentering the co zone and. as one possible solution the conditioning andfining zones Were conne l and sees" ted by a shall w c l which was reatively While this con-strucn some measure of success, re

l ourl ous p11 in arrangement "here is absolutely no obstruction to thel s in the furna e so that a in tiinum furnace output is 9.,ili6VfiLlWhile at the some costs of educing the necessary compressed air or othergas is my fraction of that necessary to supply electrical power to a.type electrodes. 0 ment, using only a small number of electrodes mountedin a specific relation to a shallow zone, does not decrease the in aceon by any material nonnt uses considerably less electrical power thanthe grid tyne electrodes which have been proposed in the past.

it is accordingly object of the present invention to provide a glassfurnace having no bridge Wall or throat.

Inited States Patent 0 di ioning zone, and a for producing a risingstream of glass in front of such a zone.

low zone and a pump for producing a rising stream of glass front of suchzone.

it is er obiect of the present invention to provice a tnroatless glassfurnace having a shallow zone and having at least one gaseous pumpadjacent the entrance to such zone.

it another object of the present invention to erovlde a throatless glassfurnace having a shallow conditi ling zone and having electrodes placedadjacent to the entrance of such zone wherein the cross ectionel area ofthe electrodes at th entrance to the shallow zone coinpa cc. to thecross sectional area of to snch zone.

object of the present invention to proglass furnace comprising a tankhaving a greater deetn than a second porrneans lo ated in the main porisnegligible 9 ss llOnlllg, l

is another SSS tion to the second portion ber4 I M lov e le cl 0-." thecor of the second portion.

it is still another obiect is a plan view 01. t furnace shown is view ofa lass furnace having a fining zones according to another embodi- Z I!plui ality oi ment of the invention;

4 is a vertical cross section taken along the of FlGURE 2;

5 a vertical cross section of a glass furnace lzing electrodes accordingto another embodiment of inven on view of th furpece of Eli 7 is ahorizontal section of a glass furnace er embodiment of he invention; and8 a vertical section of the furnace of Referring to i having side endWall is attach prises a hotter tioning zone is 1 there is seen a glassfurnace 2, an end Wall 1 2 and a submerged row Working or conditioningzone submerged Wall j and coin- "Ihis condiand end Well ;d with aWithdrawal orifice 24 and the furnace has a plurality of bubthereinpreferably in the pnrnpcr 7 my copending apolicetion No. 5"5,6"'2 nonabandon i iccording to that apelication bubbler tn es are placed in aclosed configuiation and are spaced :1 distance equal to substantially tthe dit the bubbles at the time they leave the orifices. operation lassenters the shallow conditioning zone the entrance thereto at tl esurrace of the glass mass dc large enough to provide the Withdrawalorifice with the desired volume of glass. The bubbler nrovicle a risingstream of cobbles which rising current of glass ning out at the surfacetile glass as shown at This action produces a strong glass current atthe surface of the glass mass which forces any unmelted particles ofglass back towards the melting zone and effectively prevents suchunmelted glass from entering the shallow working or conditioning zone.The arrangement of the gaseous pump and the shallow working zone is suchthat the maximum effect of the ascending glass currents is exercisedright at the inlet to the working Zone to provide a highly efficientrejection of unmelte-d glass.

The embodiment of the invention shown in FIGURES 1 and 2 is particularlywell adapted to existing furnaces since the only modification necessaryis the removal of the bridge wall and the installation of the bubblers.The maximum temperature is still applied in the fining zone immediatelyadjacent the bubblers and thus no change in the heating arrangement isnecessary. That is to say, the furnace of FIGURE 1, without the bubblertube, would be a conventional furnace if provided with a bridge wall andsubmerged throat intermediate the end Wall I6 and the opposed end wallat the position of the floating batch. Such a furnace is normallydivided into a melting zone at the batch side of the bridge wall, afining zone at the other side of the bridge wall and a shallow workingor conditioning zone at 1.3. This conventional furnace may then beconverted to a furnace constructed according to the present invention bysimply installing bubbler tubes 28 and removing the bridge wall. Undersuch circumstances the bubbler tubes produce the rising stream of glassat the submerged wall which is located at the interface of the finingand working zones.

Where further furnace modification is feasible or where a furnace isbeing originally constructed, the'embodiment of the invention shown inFIGURES 7 and 8 may be used to advantage. Referring to these figures,

there is seen a furnace 13d having side Walls 132, an end wall 134- anda submerged end wall I 59. Adjacent the wall 148 there is provided ashallow fining zone 142 having a bottom wall 144 which extends outwardbeyond the fining zone beneath the conditioning zone 146. Theconditioning zone is provided with a draw-off orifice 14$ and may beprovided with a stirrer I519.

The furnace is provided with a roof 152 and with a perforated shadowwall 154 between the melting and fining zones. A plurality of burnersenter the side walls of the fining chamber. An exhaust T59 is providedin the roof 152 for removing spent gases of combustion and a port 155 isprovided in the conventional manner for introduction of batch into themelting zone. A pair of gaseous pumps 156a and 157 is arranged in thebottom of the tank adjacent the inlet to the shallow fining zone Inoperation hot gases of combustion are delivered to the fining zone I42from the burners 156 and these gases flow through the perforated shadowwall 154 to the mel ing zone from which they are removed by the exhaust1%. The gaseous pumps 156a and 157 produce rising streams of glassadjacent the inlet to the shallow refining zone 142 and these streamsfan out as shown at led, in the same manner as illustrated in FIGURE 1,to prevent unmelted batch from entering the shallow fining zone 142.

Referring to FIGURES 3 and 4 there is shown another embodiment of theinvention comprising a glass furnace 34- having side walls 36, an endwall 38 and a submerged end wall 40. Adjacent the wall it? there areprovided a pair of shallow fining zones 52 and 44 having side walls 46and 43 and a bottom wall 56 which extends outward beyond the workingzones beneath conditioning zones 52 and 54. A low barrier 56 is providedbetween the shallow fining zones 42 and 44 and the conditioning zones 52and 54 are provided with Withdrawal orifices S and 6t) and may beprovided with stirrers 52 and 6d.

The furnace is provided with a roof 66 and with perforated shadow walls68 and 7G in the melting zone and between the fining and conditioningzones, respectively.

A plurality of burners '72 and 74 enter the side walls as and 43 of theshallow fining zones 42 and 4-4. A further shadow wall '76 is providedbetween the fining zones 42 and and the conditioning zones 52 and 54 andthis wall is substantially aligned with the end wall 78 of the finingzones. An exhaust fill is provided in the roof 66 in the melting zonefor removal of the spent gases of combustion and an opening 82 isprovided in the conventional manner for introduction of batch into themelting zone. A pair of gaseous pumps 84 and 86 is arranged in the tankfloor adjacent the inlet to each of the shallow fining zones 42 and 44.

In operation hot gases of combustion are delivered to the fining zones42 and 44 by the burners '72 and 74 and these gases flow through theperforated shadow walls 70 and as to the melting zone from which theyare removed by the exhaust 8%). The gaseous pumps 34 and 86 producerising streams of glass adjacent the inlets to the shallow fining zones42 and 4d and these streams produce a fanning action, indicated at 88,in the same manner as described in connection with FIGURES 1 and 2. Thisaction pre vents unmelted glass from entering the shallow fining zones4-2 and 44- which are immediately adjacent to the gaseous pumps and tothe surface of the glass mass. Where it is desired to utilize the glassfurnace 34 to produce colored glass, colorant may be introduced into thefining zones through ports 90 from which it is fed to the conditioningzones 52 and 54 to be fully mixed by the stirrers 62 and 64.

The greatest temperature in this furnace is provided in the fining zones42 and 44 and the gases of combustion fiow from here through the furnacein a direction counter to the movement of the glass mass.

The gases of combustion thus flow through the perforated shadow walls 70and 68 and these walls act to minimize transfer of heat throughradiation. A large difference in temperature is thus maintained betweenthe fining zones 42 and 44 in the melting zone without a large heat lossthrough radiation. The shadow walls may preferably be of the type havingnon-line of sight passages therethrough.

Referring to FIGURES 5 and 6 there is shown a still further embodimentof the invention generally similar to that seen in FIGURES 1 and 2. Thisembodiment comprises a glass furnace X2. having an end wall 94, bottomwall 96, submerged end wall 98, and side walls 100. A shallowconditioning zone 1fi2 comprising a bottom wall Itld and side walls 1%is attached to the submerged end wall 98 and is provided with awithdrawal orifice 108. This furnace is of the type which would normallycontain a bridge wall dividing the deeper portion of the tank intomelting and fining zones as discussed in connection with FIGURES 1 and2. According to the invention, however, this wall is removed and a pairof electrodes and 112 is mounted adjacent the inlet to the shallowconditioning zone. These electrodes preferably do not extend above theupper surface 114 of the bottom wall 104 of the shallow conditioningzone 102.

In operation electrical power is supplied to the electrodes 11d and 112and they create a localized heating effect adjacent the entrance to theconditioning zone 102 to create a rising current of glass which fans outat the surface of the glass mass as shown at 116. This rising currentand fanning action acts as in the embodiment of FIG- URES 1 and 2 toprevent any unmelted batch from entering the conditioning zone 102. Itwill be seen from reference to FIGURE 5 that the placement of theelectrodes 11d and 112 so that they do not rise above the upper surface114 of the bottom wall N4 of the conditioning zone ltlZ permits thefurnace to be utilized at full capacity without the electrodesexercising a physical barrier action to decrease the flow of glass. Inaddition, the entrance to the conditioning zone is so placed withrelation to the rising current of glass as to allow the rising currentto exercise a maximum glass current barrier action in preventingunmelt-ed batch from entering the conditioning zone. Since theelectrodes do not rise above the inlet to the conditioning zone a largenumber may be used Without decreasing the flow of glass. While verticalelectrodes are illustrated, it will be obvious to those skilled in theart that horizontal or inclined electrodes may also be used so long asthey do not impede the fiow of glass into the conditioning zone.

it will be apparent from the foregoing that I have provided a fullcapacity throatless glass furnace wherein unmelted batch is preventedfrom entering the conditioning zone. The energy necessary to achievethis is obtained at a minimum expense and furnace output is notdiminished in any respect.

The invention may be embodied in other specific forms without departingfrom the spirit or essential characteristics thereof. The presentembodiments are therefore to he considered in all respects asillustrative and not restriclive, the scope of the invention beingindicated by the appended claims rather than by the foregoingdescription, and all changes which come within the meaning and range ofequivalency of the claims are therefore intended to be embraced therein.

What is claimed and desired to be secured by United States LettersPatent is:

1. A throatless glass furnace comprising in combination a tank formingmelting, fining and conditioning zones which are in communiaction withone another at the surface of a glass mass in said tank, said finingzone having a greater depth than the contiguous shallow conditioningzone, said change in depth being effected by a submerged Wall, and meanssubstantially at the floor of said fining zone adjacent said submergedwall for creating a stream of molten glass rising from the bottom of saifining zone along said submerged Wall to the surface of the glass masswhere it mushrooms out to create an unimpeded fiow of surface glasstowards said melting zone, said rising stream of molten glass and saidflow of surface glass serving to prevent unmolten batch from enteringsaid conditioning zone.

2. A throatless glass furnace as set out in claim 1 wherein said meansfor creating a stream of molten glass comprises bubble producing means.

3. A throatless glass furnace as set out in claim 1 Wherein said meansfor creating a stream of molten glass comprises bubble producing meansarranged in at least one closed configuration wherein the individualbubble producing means in said configuration cooperate to provide asingle rising stream of molten glass which mushrooms out at the surfaceof the glass mass.

A throatless glass furnace as set out in claim 1 wherein said means forcreating a stream of molten glass comprises electrode means forproducing Joule effect heat.

5. A throatl ss glass furnace comprising in combination, a tank forcontaining a glass mass and forming melting, fining and conditioningzones which are in communication with one another at the surface of saidglass mass, said melting and finin zones having a first depth, saidconditioning zone havin a second depth, bottom walls for each of saidzones, the bottom wall for said conditioning zone being at a higherlevel than the bottom walls of said melting and fining zones andconnected to the bottom wall of said fining zone by means of an end wallsubmerged in said glass mass, and means substantially at the bottom Wallof said firing zone adjacent said end wall for creating a stream ofmolten glass rising from the bottom of said fining zone to the surfaceof the glass mass where it mushrooms out to create an unimpeded flow ofsurface glass towards said melting zone, said rising stream of moltenglass and said how of surface glass serving to prevent unmolten batchfrom entering said conditioning zone.

References tilted by the Examiner UNUSED STATES PATENTS 1,832,063 11/31Thompson 65-336 1,870,242 8/32 Drake 263-15 1,880,541 10/32 Wadrnan65-135 1,937,390 11/33 McKinley et al. 65-135 1,941,779 1/34 Amsler65-137 1,953,034 3/34 Willetts 65-335 2,162,983 6/39 Sullivan 65-346 X2,203,269 6/40 Mulholland 65-135 2,225,616 12/40 Borel 13-6 2,313,2173/43 Borel 65-347 2,387,222 10/45 Wright 65-22 2,593,197 4/52 Rough65-335 X 2,616,221 11/52 Hanson 65-178 2,773,111 12/56 Arbeit et al65-136 X FOREIGN PATENTS 611,401 10/48 Great Britain.

DONALL H. SYLVESTER, Primary Examiner.

WILLIAM J. STEPHENSON, CHARLES R. HODGES, MICHAEL V. BRINDXSI, BENJAMINBENDETT, IVAN R. LADY, MORRIS O. WOLK, Examiners.

UNITED STATES PATENT OFFICE CERTIFICATE OF CORRECTION Patent No.3,198,618 August 3, 1965 Harvey L. Penberthy It is hereby certified thaterror appears in the above numbered patent requiring correction and thatthe said Letters Patent should read as corrected below.

Column 1, line 28, for "condition" read conditioning column 5, line 29,for "communiaction" read communication column 6, line 17, for "firing"read fining Signed and sealed this 26th day of April 1966.

(SEAL) Attest:

ERNEST W. SWIDER Attesting Officer EDWARD J. BRENNER Commissioner ofPatents

1. A THROATLESS GLASS FURNACE COMPRISING IN COMBINATION A TANK FORMINGMELTING, FINING AND CONDITIONING ZONES WHICH ARE IN COMMUNICATION WITHONE ANOTHER AT THE SURFACE OF A GLASS MASS IN SAID TANK, SAID FININGZONE HAVING A GREATER DEPTH THAN THE CONTIGUOUS SSHALLOW CONDITIONINGZONE, SAID CHANGE IN DEPTH BEING EFFECTED BY A SUBMERGED WALL, AND MEANSSUBSTANTIALLY AT THE FLOOR OF SAID FINING ZONE ADJACENT SAID SUBMERGEDWALL FOR CREATING A STREAM OF MOLTEN GLASS RING FROM THE BOTTOM OF SAIDFINING ZONE ALONG SAID SUBMERGED WALL TO THE SURFACE OF THE GLASS MASSWHERE IT MUSHROOMS OUT TO CREATE AN UNIMPEDED FLOW OF SURFACE GLASSTOWARDS SAID MELTING ZONE, SAID RISING STREAM OF MOLTEN GLASS AND SAIDFLOW OF SURFACE GLASS SERVING TO PREVENT UNMOLTEN BATCH FROM ENTERINGSAID CONDITIONING ZONE.